let bird = {
    name: "Donald",
    numLegs: 2
};

let boat = {
    name: "Warrior",
    type: "race-boat"
};

// 请把你的代码写在这条注释以下
function glideMixin(obj) {
    obj.glide = function() {
        return "Gliding wooosh!";
    };
}

glideMixin(bird);
glideMixin(boat);
